Bilateral mastoiditis from red tide exposure.

ABSTRACT

BACKGROUND: Bilateral mastoiditis in adults has previously been reported only in association with diabetes mellitus or immunocompromised patients. OBJECTIVES: To describe a case of bilateral mastoiditis in a healthy adult and to investigate the etiology. CASE REPORT A 53-year-old woman presented to the Emergency Department with bilateral otitis externa and mastoiditis after scuba diving during a harmful algal bloom, commonly known as a "red tide." The levels of coliform bacteria recorded at the time and location of her dive exceeded health regulatory limits and correlate with her atypical culture results. CONCLUSION: Elevated bacterial counts that result from harmful algal blooms may account for this rare infection.